When an atrio-ventricular cardiac valve, such as a tricuspid or mitral valve, is diseased, it may be replaced by heart valve prosthesis. Such heart valve prostheses may include mechanical heart valves, natural tissue heart valves, or combinations thereof. A surgical procedure for replacing such a valve poses a serious risk and usually requires placing the patient on cardiopulmonary bypass during the procedure. With a patient on cardiopulmonary bypass, the surgical procedure is not only more difficult, but also poses a greater risk of morbidity and mortality to the patient. Such risks increase when a patient has been diagnosed with mitral or pulmonic valve stenosis or insufficiency.